import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../core/providers/auth_provider.dart';
import '../../core/theme/app_theme.dart';
import '../../models/tenant.dart';
import 'tenant_team_repository.dart';

class TenantTeamScreen extends ConsumerStatefulWidget {
  const TenantTeamScreen({super.key});

  @override
  ConsumerState<TenantTeamScreen> createState() => _TenantTeamScreenState();
}

class _TenantTeamScreenState extends ConsumerState<TenantTeamScreen> {
  List<TeamMember> _members = [];
  bool _loading = true;
  String? _error;

  @override
  void initState() {
    super.initState();
    _load();
  }

  Future<void> _load() async {
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      final tenantId = ref.read(authProvider).activeTenant!.tenant.id;
      final members = await TenantTeamRepository.instance.listMembers(tenantId);
      if (mounted) {
        setState(() {
          _members = members;
          _loading = false;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _error = e.toString();
          _loading = false;
        });
      }
    }
  }

  bool get _canManage =>
      ref.read(authProvider).activeTenant?.canManageUsers ?? false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Ekip'),
        actions: [
          if (_canManage)
            TextButton.icon(
              onPressed: () => _showAddMemberSheet(context),
              icon: const Icon(Icons.person_add_outlined, size: 18),
              label: const Text('Üye Ekle'),
            ),
        ],
      ),
      body: _loading
          ? const Center(child: CircularProgressIndicator())
          : _error != null
              ? _ErrorView(error: _error!, onRetry: _load)
              : RefreshIndicator(
                  onRefresh: _load,
                  child: ListView(
                    padding: const EdgeInsets.all(16),
                    children: [
                      _SectionHeader(
                        title: 'Üyeler',
                        count: _members.length,
                      ),
                      const SizedBox(height: 8),
                      _MembersList(
                        members: _members,
                        canManage: _canManage,
                        currentUserId:
                            ref.read(authProvider).profile?.id ?? '',
                        onRoleChange: _changeRole,
                        onRemove: _removeMember,
                      ),
                      const SizedBox(height: 24),
                    ],
                  ),
                ),
    );
  }

  Future<void> _showAddMemberSheet(BuildContext context) async {
    final tenantId = ref.read(authProvider).activeTenant!.tenant.id;
    await showModalBottomSheet<void>(
      context: context,
      isScrollControlled: true,
      backgroundColor: AppColors.background,
      shape: const RoundedRectangleBorder(
        borderRadius: BorderRadius.vertical(top: Radius.circular(20)),
      ),
      builder: (_) => _AddMemberSheet(
        onAdd: (firstName, lastName, email, password, role) async {
          await TenantTeamRepository.instance.addMember(
            tenantId: tenantId,
            email: email,
            password: password,
            firstName: firstName,
            lastName: lastName,
            role: role,
          );
          await _load();
        },
      ),
    );
  }

  Future<void> _changeRole(TeamMember member, TenantRole newRole) async {
    try {
      await TenantTeamRepository.instance.changeMemberRole(
          member.memberId, newRole);
      await _load();
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context)
            .showSnackBar(SnackBar(content: Text('Hata: $e')));
      }
    }
  }

  Future<void> _removeMember(TeamMember member) async {
    final name = member.user.displayName.isNotEmpty
        ? member.user.displayName
        : member.user.email;
    final confirmed = await showDialog<bool>(
      context: context,
      builder: (_) => AlertDialog(
        title: const Text('Üyeyi Çıkar'),
        content: Text('$name adlı üyeyi ekipten çıkarmak istiyor musunuz?'),
        actions: [
          TextButton(
              onPressed: () => Navigator.pop(context, false),
              child: const Text('Vazgeç')),
          FilledButton(
            onPressed: () => Navigator.pop(context, true),
            style: FilledButton.styleFrom(backgroundColor: AppColors.cancelled),
            child: const Text('Çıkar'),
          ),
        ],
      ),
    );
    if (confirmed != true) return;
    try {
      await TenantTeamRepository.instance.removeMember(member.memberId);
      await _load();
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context)
            .showSnackBar(SnackBar(content: Text('Hata: $e')));
      }
    }
  }
}

// ── Section header ─────────────────────────────────────────────────────────

class _SectionHeader extends StatelessWidget {
  const _SectionHeader({required this.title, required this.count});
  final String title;
  final int count;

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Text(
          title,
          style: const TextStyle(
            fontSize: 13,
            fontWeight: FontWeight.w700,
            color: AppColors.textSecondary,
            letterSpacing: 0.5,
          ),
        ),
        const SizedBox(width: 8),
        Container(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 2),
          decoration: BoxDecoration(
            color: AppColors.inProgressBg,
            borderRadius: BorderRadius.circular(20),
          ),
          child: Text(
            '$count',
            style: const TextStyle(
              fontSize: 12,
              fontWeight: FontWeight.w700,
              color: AppColors.inProgress,
            ),
          ),
        ),
      ],
    );
  }
}

// ── Members list ───────────────────────────────────────────────────────────

class _MembersList extends StatelessWidget {
  const _MembersList({
    required this.members,
    required this.canManage,
    required this.currentUserId,
    required this.onRoleChange,
    required this.onRemove,
  });

  final List<TeamMember> members;
  final bool canManage;
  final String currentUserId;
  final Future<void> Function(TeamMember, TenantRole) onRoleChange;
  final Future<void> Function(TeamMember) onRemove;

  @override
  Widget build(BuildContext context) {
    if (members.isEmpty) {
      return const _EmptyCard(message: 'Henüz üye yok.');
    }
    return Container(
      decoration: BoxDecoration(
        color: AppColors.surface,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: AppColors.border),
        boxShadow: [
          BoxShadow(
              color: Colors.black.withValues(alpha: 0.05),
              blurRadius: 12,
              offset: const Offset(0, 4))
        ],
      ),
      child: Column(
        children: members.asMap().entries.map((entry) {
          final i = entry.key;
          final m = entry.value;
          final isLast = i == members.length - 1;
          return _MemberTile(
            member: m,
            isSelf: m.user.id == currentUserId,
            canManage: canManage && m.role != TenantRole.owner,
            showDivider: !isLast,
            onRoleChange: (role) => onRoleChange(m, role),
            onRemove: () => onRemove(m),
          );
        }).toList(),
      ),
    );
  }
}

class _MemberTile extends StatelessWidget {
  const _MemberTile({
    required this.member,
    required this.isSelf,
    required this.canManage,
    required this.showDivider,
    required this.onRoleChange,
    required this.onRemove,
  });

  final TeamMember member;
  final bool isSelf;
  final bool canManage;
  final bool showDivider;
  final void Function(TenantRole) onRoleChange;
  final VoidCallback onRemove;

  @override
  Widget build(BuildContext context) {
    final name = member.user.displayName.isNotEmpty
        ? member.user.displayName
        : member.user.email;
    final initials = name.trim().isNotEmpty
        ? name.trim()[0].toUpperCase()
        : '?';

    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        Padding(
          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
          child: Row(
            children: [
              Container(
                width: 40,
                height: 40,
                decoration: BoxDecoration(
                  color: AppColors.inProgressBg,
                  borderRadius: BorderRadius.circular(20),
                ),
                child: Center(
                  child: Text(
                    initials,
                    style: const TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.w700,
                      color: AppColors.inProgress,
                    ),
                  ),
                ),
              ),
              const SizedBox(width: 12),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Row(
                      children: [
                        Text(
                          name,
                          style: const TextStyle(
                            fontWeight: FontWeight.w600,
                            color: AppColors.textPrimary,
                          ),
                        ),
                        if (isSelf) ...[
                          const SizedBox(width: 6),
                          Container(
                            padding: const EdgeInsets.symmetric(
                                horizontal: 6, vertical: 1),
                            decoration: BoxDecoration(
                              color: AppColors.successBg,
                              borderRadius: BorderRadius.circular(6),
                            ),
                            child: const Text(
                              'Sen',
                              style: TextStyle(
                                fontSize: 10,
                                fontWeight: FontWeight.w700,
                                color: AppColors.success,
                              ),
                            ),
                          ),
                        ],
                      ],
                    ),
                    Text(
                      member.user.email,
                      style: const TextStyle(
                        fontSize: 12,
                        color: AppColors.textSecondary,
                      ),
                    ),
                  ],
                ),
              ),
              if (canManage) ...[
                _RoleChip(
                  role: member.role,
                  onChanged: onRoleChange,
                ),
                const SizedBox(width: 4),
                IconButton(
                  onPressed: onRemove,
                  icon: const Icon(Icons.remove_circle_outline,
                      color: AppColors.cancelled, size: 20),
                  tooltip: 'Çıkar',
                  constraints: const BoxConstraints(),
                  padding: const EdgeInsets.all(6),
                ),
              ] else
                _RoleBadge(role: member.role),
            ],
          ),
        ),
        if (showDivider)
          const Divider(height: 1, indent: 68, color: AppColors.border),
      ],
    );
  }
}

class _RoleChip extends StatelessWidget {
  const _RoleChip({required this.role, required this.onChanged});
  final TenantRole role;
  final void Function(TenantRole) onChanged;

  static const _selectableRoles = [
    TenantRole.admin,
    TenantRole.technician,
    TenantRole.delivery,
    TenantRole.finance,
    TenantRole.doctor,
    TenantRole.member,
  ];

  @override
  Widget build(BuildContext context) {
    return PopupMenuButton<TenantRole>(
      initialValue: role,
      onSelected: onChanged,
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
      itemBuilder: (_) => _selectableRoles
          .map((r) => PopupMenuItem(
                value: r,
                child: Text(r.label),
              ))
          .toList(),
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 5),
        decoration: BoxDecoration(
          color: _roleBg(role),
          borderRadius: BorderRadius.circular(8),
        ),
        child: Row(
          mainAxisSize: MainAxisSize.min,
          children: [
            Text(
              role.label,
              style: TextStyle(
                fontSize: 12,
                fontWeight: FontWeight.w600,
                color: _roleColor(role),
              ),
            ),
            const SizedBox(width: 4),
            Icon(Icons.arrow_drop_down, size: 16, color: _roleColor(role)),
          ],
        ),
      ),
    );
  }
}

class _RoleBadge extends StatelessWidget {
  const _RoleBadge({required this.role});
  final TenantRole role;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 5),
      decoration: BoxDecoration(
        color: _roleBg(role),
        borderRadius: BorderRadius.circular(8),
      ),
      child: Text(
        role.label,
        style: TextStyle(
          fontSize: 12,
          fontWeight: FontWeight.w600,
          color: _roleColor(role),
        ),
      ),
    );
  }
}

Color _roleBg(TenantRole r) => switch (r) {
      TenantRole.owner => AppColors.inProgressBg,
      TenantRole.admin => AppColors.inProgressBg,
      TenantRole.doctor => AppColors.successBg,
      _ => AppColors.surface,
    };

Color _roleColor(TenantRole r) => switch (r) {
      TenantRole.owner => AppColors.inProgress,
      TenantRole.admin => AppColors.inProgress,
      TenantRole.doctor => AppColors.success,
      _ => AppColors.textSecondary,
    };

// ── Add member sheet ────────────────────────────────────────────────────────

class _AddMemberSheet extends StatefulWidget {
  const _AddMemberSheet({required this.onAdd});
  final Future<void> Function(
    String firstName,
    String lastName,
    String email,
    String password,
    TenantRole role,
  ) onAdd;

  @override
  State<_AddMemberSheet> createState() => _AddMemberSheetState();
}

class _AddMemberSheetState extends State<_AddMemberSheet> {
  final _formKey = GlobalKey<FormState>();
  final _firstNameController = TextEditingController();
  final _lastNameController = TextEditingController();
  final _emailController = TextEditingController();
  final _passwordController = TextEditingController();
  TenantRole _selectedRole = TenantRole.member;
  bool _saving = false;
  bool _obscurePassword = true;

  static const _selectableRoles = [
    TenantRole.admin,
    TenantRole.technician,
    TenantRole.delivery,
    TenantRole.finance,
    TenantRole.doctor,
    TenantRole.member,
  ];

  @override
  void dispose() {
    _firstNameController.dispose();
    _lastNameController.dispose();
    _emailController.dispose();
    _passwordController.dispose();
    super.dispose();
  }

  Future<void> _submit() async {
    if (!_formKey.currentState!.validate()) return;
    setState(() => _saving = true);
    try {
      await widget.onAdd(
        _firstNameController.text.trim(),
        _lastNameController.text.trim(),
        _emailController.text.trim(),
        _passwordController.text,
        _selectedRole,
      );
      if (mounted) Navigator.pop(context);
    } catch (e) {
      if (mounted) {
        final msg = _friendlyError(e);
        ScaffoldMessenger.of(context)
            .showSnackBar(SnackBar(content: Text(msg)));
      }
    } finally {
      if (mounted) setState(() => _saving = false);
    }
  }

  static String _friendlyError(Object e) {
    final s = e.toString();
    if (s.contains('email') && s.contains('unique')) {
      return 'Bu e-posta adresi zaten kayıtlı.';
    }
    final msgMatch = RegExp(r'message: ([^,}]+)').firstMatch(s);
    if (msgMatch != null) return msgMatch.group(1)!.trim();
    if (s.length > 120) return 'Sunucu hatası';
    return s;
  }

  @override
  Widget build(BuildContext context) {
    final bottom = MediaQuery.of(context).viewInsets.bottom;
    return Padding(
      padding: EdgeInsets.fromLTRB(24, 24, 24, 24 + bottom),
      child: Form(
        key: _formKey,
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                const Text(
                  'Üye Ekle',
                  style: TextStyle(
                    fontSize: 20,
                    fontWeight: FontWeight.w700,
                    color: AppColors.textPrimary,
                  ),
                ),
                const Spacer(),
                IconButton(
                  onPressed: () => Navigator.pop(context),
                  icon: const Icon(Icons.close),
                ),
              ],
            ),
            const SizedBox(height: 20),
            Row(
              children: [
                Expanded(
                  child: TextFormField(
                    controller: _firstNameController,
                    textCapitalization: TextCapitalization.words,
                    textInputAction: TextInputAction.next,
                    decoration: const InputDecoration(
                      labelText: 'İsim',
                      prefixIcon: Icon(Icons.person_outline),
                    ),
                    validator: (val) {
                      if (val == null || val.trim().isEmpty) return 'Zorunlu';
                      return null;
                    },
                  ),
                ),
                const SizedBox(width: 12),
                Expanded(
                  child: TextFormField(
                    controller: _lastNameController,
                    textCapitalization: TextCapitalization.words,
                    textInputAction: TextInputAction.next,
                    decoration: const InputDecoration(
                      labelText: 'Soyisim',
                    ),
                    validator: (val) {
                      if (val == null || val.trim().isEmpty) return 'Zorunlu';
                      return null;
                    },
                  ),
                ),
              ],
            ),
            const SizedBox(height: 16),
            TextFormField(
              controller: _emailController,
              keyboardType: TextInputType.emailAddress,
              textInputAction: TextInputAction.next,
              autocorrect: false,
              decoration: const InputDecoration(
                labelText: 'E-posta',
                hintText: 'ornek@email.com',
                prefixIcon: Icon(Icons.email_outlined),
              ),
              validator: (val) {
                if (val == null || val.trim().isEmpty) return 'E-posta zorunludur';
                if (!val.contains('@')) return 'Geçerli bir e-posta girin';
                return null;
              },
            ),
            const SizedBox(height: 16),
            TextFormField(
              controller: _passwordController,
              obscureText: _obscurePassword,
              textInputAction: TextInputAction.done,
              decoration: InputDecoration(
                labelText: 'Şifre',
                prefixIcon: const Icon(Icons.lock_outline),
                suffixIcon: IconButton(
                  icon: Icon(_obscurePassword
                      ? Icons.visibility_outlined
                      : Icons.visibility_off_outlined),
                  onPressed: () =>
                      setState(() => _obscurePassword = !_obscurePassword),
                ),
              ),
              validator: (val) {
                if (val == null || val.isEmpty) return 'Şifre zorunludur';
                if (val.length < 8) return 'En az 8 karakter olmalı';
                return null;
              },
            ),
            const SizedBox(height: 16),
            DropdownButtonFormField<TenantRole>(
              value: _selectedRole,
              decoration: const InputDecoration(
                labelText: 'Rol',
                prefixIcon: Icon(Icons.badge_outlined),
              ),
              items: _selectableRoles
                  .map((r) => DropdownMenuItem(
                        value: r,
                        child: Text(r.label),
                      ))
                  .toList(),
              onChanged: (v) {
                if (v != null) setState(() => _selectedRole = v);
              },
            ),
            const SizedBox(height: 24),
            SizedBox(
              width: double.infinity,
              child: FilledButton.icon(
                onPressed: _saving ? null : _submit,
                icon: _saving
                    ? const SizedBox(
                        width: 16,
                        height: 16,
                        child: CircularProgressIndicator(
                            strokeWidth: 2, color: Colors.white),
                      )
                    : const Icon(Icons.person_add_outlined, size: 18),
                label: const Text('Üye Ekle'),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

// ── Helpers ────────────────────────────────────────────────────────────────

class _EmptyCard extends StatelessWidget {
  const _EmptyCard({required this.message});
  final String message;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.all(24),
      decoration: BoxDecoration(
        color: AppColors.surface,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: AppColors.border),
      ),
      child: Center(
        child: Text(
          message,
          style: const TextStyle(color: AppColors.textSecondary),
        ),
      ),
    );
  }
}

class _ErrorView extends StatelessWidget {
  const _ErrorView({required this.error, required this.onRetry});
  final String error;
  final VoidCallback onRetry;

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: [
          const Icon(Icons.error_outline, color: AppColors.cancelled, size: 40),
          const SizedBox(height: 12),
          Text(error,
              style: const TextStyle(color: AppColors.textSecondary),
              textAlign: TextAlign.center),
          const SizedBox(height: 12),
          TextButton(onPressed: onRetry, child: const Text('Tekrar Dene')),
        ],
      ),
    );
  }
}